NK Jemisin is the first black winner of a Hugo award for novels.
Photograph: Laura Hanifin

The divide between high and low culture, or between what readers love and what the critics think they ought to love, is not at all clear in science fiction. The prestigious Hugo awards are conferred on the basis of what most readers have loved most. The franchise is not restrictive, although there is a fee. Such openness can be construed as an invitation to game the system, but the Hugos have a defence mechanism: if the shortlists have been swamped by an organised voting campaign, it is possible for ordinary voters to reject all the nominees in a particular category and vote for “no award”. This defence has had to be used a couple of times in recent years to fight off attempts by rightwing trolls to impose their views on the majority.

For the last three years the winning novelist has been the American NK Jemisin, for the successive volumes of her trilogy The Broken Earth. On the surface, it deals with life on a planet of ceaseless, life-threatening volcanic activity, where three different sentient life forms – one so profoundly alien that it can swim through the planet’s crust, and another consisting of multifaceted flying obelisks – must wrestle with human dilemmas. So there is plenty of excitement and explosions of the traditional sort. But it is not stocked with fantasy figures for the adolescent male. The central emotional relationships are those between a mother and her daughters, and the deep structure of the plot explores the experience of slavery and the cost and necessity of revolt. Nothing is permanent: families and cities alike are violently broken by external force. Sometimes new forms of living are built on the ruins of the old. Sometimes it is all abandoned and forgotten. The future is terrifying and the past incomprehensibly alien, yet hope, love and courage never quite die.

Ms Jemisin is the first black winner of a Hugo award for novels (the redoubtable Samuel Delany won twice for his short stories). Most of her characters are black, though this becomes only gradually apparent, and the system of slavery on her planet is not based on skin colour. Yet science fiction allows her to display some of the fundamental characteristics of any system of slavery, however much her account derives from the particular experience of African Americans. It may be the ultimate ambition of novelists to make characters who are entirely three-dimensional but in practice most of them produce bas-reliefs, where only aspects of their characters spring from the page and much of the background is undifferentiated.

It is the particular gift of genre fiction to assume a different background to the mainstream and so delineate character from a different angle. Science fiction carries this change of perspectives to extremes. By changing what counts as figure and what as background, the characters can be seen in ways otherwise impossible – and so, ultimately, we can understand ourselves in ways that would otherwise be impossible. These novels are a gift to the whole of our culture.